Tag: genetics

Camels are known for their humps, which store fat and allow camels to survive long periods of time without food or water. But camels have also developed other traits like insulin resistance and salt tolerance to help them feel more at home in extreme environments. Scientists are now working to determine what these adaptations look like on the genetic level, and they hope their results, published in Nature Communications this week, may eventually shed some light on metabolism-related diseases in humans, too.

Though the subway rats may have been able to escape the flooded tunnels during Hurricane Sandy, lab rats in basement cages weren’t so lucky. New York University lost around 10,000 research rodents from a flooded animal facility in the basement of the Smilow Research Center in Manhattan, according to The New York Times. These lab animals are genetically engineered and/or specially bred with traits that make them good models for human disorders, like cancer, heart disease, and schizophrenia. Creating such research strains can take years. Gordon Fishell, associate director of the NYU Neuroscience Institute, told the Times that he lost 10 years of work in the flood. A basement animal facility also flooded at Johns Hopkins University, in Baltimore, but staff members rescued many of the animals, ScienceInsider reported.

Our bodies are picky eaters when it comes to amino acids, and sometimes just a small screw-up can cause larger problems down the road. Scientists recently found an association between an amino-acid depleting mutation, and neurological problems in a small sample of humans. In mice with the same mutation, nutritional supplements reversed similar symptoms, offering the possibility of a treatment for the human disorder in the future. The results appeared in the journal Science. Read More

The hard-working precursor cells that produce sperm just can’t catch a break. Since men make sperm throughout their lives, these cells have to divide again and again, sending one copy of themselves off to become sperm cells each time. DNA doesn’t always copy itself perfectly, so over the years, genetic errors pile up. And now a new study has quantified just how many mutations sperm will accumulate—and pass on to any offspring—for fathers of various ages. Scientists think that these mutations may be partly to blame for the fact that children with older fathers tend to have higher rates of bipolar disorder, schizophrenia, and autism.

What’s the News: Have you ever wondered what is going on in your body at the molecular level when you’re sick? If you could see which medications, whether for treating cold symptoms or cancer, had an effect on you, and whether changing your diet, exercise, or some other factor would increase their effectiveness, you’d gain a lot of power over your body.

This kind of detailed information would start with getting your genome sequenced, but it wouldn’t stop there. It would require a constant stream of information about which genes are being expressed, at what levels, and in what tissues, and what else is going with your metabolism. That level of granularity has been the goal of geneticist Michael Snyder’s work and it has yielded a striking new paper: Snyder’s team analyzed samples of his own blood, taken over the course of 14 months, and were able to watch in real-time as the geneticist developed type 2 diabetes and successfully arrested its progress.

The Clinic for Special Children is “probably the only medical centre today with both a hitching post and an Ion Torrent DNA sequencer,” writes Trisha Gura in a Nature profile of the clinic. In the heart of Amish and Mennonite territory in Pennsylvania, it serves a population known best for technologies like the horse and buggy. Yet this might just be the frontier for personalized genomic medicine.

Genomic medicine promises, among other things, to diagnosis rare diseases by looking at an individual person’s DNA mutations. Genome sequencing was used to diagnose a boy’s mysterious illness for the first time in 2010. However the long process of his diagnosis, as highlighted in the Milwaukee Journal Sentinel’s Pulitzer Prize-winning coverage, also proves how difficult genomic medicine is: Compare the genomes of any two people and you’ll find tens of thousands of differences. “We’ve talked about the thousand-dollar genome and the million-dollar interpretation,” says genomicist Eric Topol, to Nature. “The challenging bottleneck is the process of trying to nail down which DNA variation is the root cause.”

Digging around in your DNA is getting cheaper and easier all the time. For only $207, you can now subscribe to 23andMe’s genotyping service, for instance, which gives you information about your genetic background, potential disease susceptibilities, and other traits. And as the numbers of people in such companies’ databases climb into the hundreds of thousands, it has become possible for software to connect customers who share so much DNA, they may well be relatives. For adoptees who don’t have access to their adoption records and are curious about biological family, there’s never been a better time to go searching. The New York Timesfollows the story of one 42-year-old woman who, after learning she was adopted, finds her third cousin through a DNA service, and details the relationship that they form as she deals with the revelation that she is not, after all, the daughter of her adoptive parents.

About five weeks after shipping off two tiny vials of her cells from a swab of her cheek, Mrs. Vaughan received an e-mail informing her that her bloodlines extended to France, Romania and West Africa. She was also given the names and e-mail addresses of a dozen distant cousins. This month, she drove 208 miles from her hometown here to Evansville, Ind., to meet her third cousin, the first relative to respond to her e-mails. Mrs. Vaughan is black and her cousin is white, and they have yet to find their common ancestor. But Mrs. Vaughan says that does not matter.

“Somebody is related to me in this world,” she said. “Somebody out there has my blood. I can look at her and say, ‘This is my family.’ ”

Artist’s rendering of a mitochondrian, the energy-producing
cellular structure affected by ARSACS

Scientists have pinpointed the cause of a rare, fatal neurodegenerative disorder called ARSACS, or autosomal recessive spastic ataxia of Charlevoix-Saguenay. The disease is due to defects in neuron’s mitochondria, the bit of biological machinery that generates energy for the cell—a structure known to be affected in Parkinson’s, Alzheimer’s, and other neurological diseases, as well.

ARSACS was first observed in the descendants of a small group of 17th century French settlers who made their homes near the Charlevoix and Saguenay rivers in what is now Quebec, and has since been seen worldwide. But its incidence remains unusually high in that particular French Canadian community, with 1 in 1,500 to 2,000 people developing ARSACS and 1 in 23 people unaffected genetic carriers of the disease.

In 2006, the Genomics X Prize competition was announced: $10 million for sequencing 100 human genomes in 10 days for $10,000 apiece, to be kicked off in 2013. The idea was to spur innovation in technology by asking the (currently) impossible, the hallmark of the X Prize Foundation.

But while sequencing has gotten cheap, it hasn’t gotten all that much faster in the last five years, and none of the eight teams who signed up have ever gotten to the point where such a short time span could be feasible. So, Archon and Medco, the two companies funding the competition, have revamped the requirements. This week they’ve announced the new, improved Genomics X prize: $10 million for sequencing 100 human genomes in 30 days—but for $1,000 apiece. (Currently, getting your genome sequenced commercially runs about $5000 at the cheapest.) The new version of the competition, which will kick off on January 3, 2013, also has clearer standards for judging: the genomes have to be 98 percent complete and have no more than one error per million nucleotides.